The present invention relates to sealing boots, and more particularly to a sealing boot of elastomeric material for hermetically closing an annular opening between support and movable members in relatively reciprocable relationship, the sealing boot including a bellows portion which is integrally formed at the opposite ends thereof with a pair of cylindrical sealing portions respectively attached to the support and movable members.
In general, such a sealing boot as described above has been adapted for use with sliding portion in an hydraulically operated disc brake assembly of the pin-slide type, a sliding portion in a piston and wheel cylinder assembly or the like to prevent entry of water and dirt into an annular opening at the sliding portion. For example, in a conventional sealing boot as shown in FIG. 7, a cylindrical sealing portion 2 integrally formed therewith has a cylindrical sealing surface 2a to be tightly attached within an annular groove 1a of a pin-bush 1 and an inner side-surface 2b substantially perpendicular to the inner end 2a.sub.1 of surface 2a. When, upon assembly, the pin-bush 1 is inserted in the direction of the arrow in the figure, the cylindrical sealing portion 2 is inverted in the annular groove 1a due to abutment against a tapered end of pin-bush 1 at its inner side-surface 2b and remains as it is. This requires attachment of the cylindrical sealing portion 2 within the annular groove 1a by hand as is illustrated by an imaginary line in the figure, resulting in time consumption during the assembling process of the sealing boot.